Martin Johnson gave his work in progress another lick or two of paint yesterday by adding a couple of uncapped backs to his England squad for the forthcoming Six Nations Championship, which begins with a profoundly uncomfortable fixture against Wales at Twickenham in a little over three weeks' time. If Chris Ashton, the Northampton wing, was selected on form – he is, after all, the Premiership's leading scorer – Shontayne Hape, the Bath centre, owed his promotion to a risky combination of guesswork and assumption.

The move for Hape, a Maori from New Zealand with a background in rugby league and fewer than 40 games of union under his belt, cost Shane Geraghty his place in the elite party – a bitter moment for the goal-kicking playmaker who started last November's matches against Australia and Argentina as Johnson's new-age inside centre. Now, it seems, Geraghty is not considered to be an inside centre of any description. "We think he's primarily an outside-half," the manager said, and while Jonny Wilkinson is upright and injury-free, outside-half is not a position with much of a future attached to it.

Geraghty's first season alongside Ashton at Franklin's Garden's is not panning out in quite the way he imagined when he made the switch from London Irish: he has yet to nail the No 10 position ahead of Stephen Myler, with whom he will spend the next few representative weeks in the second-string England Saxons squad, and has had precious little opportunity to stake his claim as his club's first-choice No 12. Once again, a richly talented English midfielder finds himself betwixt, between and, momentarily at least, bereft.

Mathew Tait, one of the two or three most dangerous broken-field runners in the country, will know precisely how Geraghty feels, but happily the Sale player also understands that the wheels of fortune turn full circle. After a long period of being messed around positionally – England have attempted to turn him into a full-back and a wing while ignoring what Basil Fawlty would have called the "bleedin' obvious" – he is now officially viewed as the outside centre he was when Andy Robinson first capped him as a teenager in 2006. He may even start against Wales, ahead of Dan Hipkiss.

"Things change," Johnson explained when asked about his latest thinking on the issue. "We see Matt as a 13 and he'll definitely be in there competing for a starting place against the Welsh. If I'm honest, I've felt for him a little. At times, it's been very convenient to put him on the bench as cover for a number of positions. Now, with an improving situation at full-back and on the wing, we're looking at him differently."

With Toby Flood and Riki Flutey back in the thick of it after long-term injuries, the misfiring midfield suddenly looks as though it might be armed with something more lethal than blanks. Ayoola Erinle, controversially picked ahead of Geraghty for the last autumn Test against New Zealand, has been dropped completely – an admission, albeit unspoken, that the selection of so limited a player in a key decision-making position was an act of narrow-minded folly.

If there was a debit side to yesterday's announcement, it was that Johnson has done nothing to address serious concerns surrounding the England scrum. Tim Payne of Wasps, humiliated by a rampant Leicester set-piece last Saturday, is still in the senior squad, and with Andrew Sheridan recovering from a dislocated shoulder, he remains the favourite to face Wales, who expect to have the highly effective Lions tight-head prop Adam Jones in their front row at Twickenham. The two form props in England, the Bath loose-head specialist David Flatman and the Leicester tight-head newcomer Dan Cole have not been chosen, although the former still has a chance of featuring when the selectors complete the formality of ruling Sheridan out of the Six Nations later this month.

Largely as a consequence of the labyrinthine terms of the player-release agreement between England and the Premiership clubs, a number of injured players are still in the front-line and Saxons squads, even though they have little or no chance of starting the Six Nations or playing in the imminent second-string internationals against Ireland A and Italy A. These include two Leicester players, the scrum-half Harry Ellis and Julian White, in the senior group, along with the uncapped London Irish front-rower Alex Corbisiero and the more experienced Wasps flanker Tom Rees in the junior one.

There was more in the way of mystification when Johnson declined to confirm Steve Borthwick, his current captain, as captain for the first important Test business of the new decade. "We'll name our captain as we get closer to the tournament," the manager said, cryptically, without giving the slightest indication that the Saracens lock might be relieved of his position. "Steve has done a great job for us, but everyone is competing for places in the team and this is how we've gone about it in the past. It's the way Steve himself would want it."

At this distance Johnson seems certain to make a number of changes to the side beaten by the All Blacks two months ago. Assuming Delon Armitage resumes at full-back, Mark Cueto and Ugo Monye are likely to be the first-choice wings, ahead of Matt Banahan. Flutey will certainly reclaim one of the centre positions and there is likely to be a recall for Nick Easter of Harlequins at No 8. What happens in the front row, God only knows. There is an awful lot to play for in that department over the coming weekends.

Not that Johnson appeared unduly concerned yesterday. "We had injuries on an unprecedented scale in the autumn, but now we have a squad capable of going into any Six Nations game thinking about winning it," he said. "There will be an awful lot of hype surrounding the Wales game and it will generate huge intensity. We'll have to be smart, but like us, the Welsh are under a little pressure after a disappointing autumn."